The present invention relates to a semiconductor laser module and a method of making the same.
In general, the semiconductor laser module includes a high-purity inert gas injected thereinto and a hermetic seal formed through a seam welding or the like. This is because if the atmosphere in the interior of the package which contacts the semiconductor laser element contains moisture or organic matter, the semiconductor laser element may seriously be impaired in reliability by short-circuiting due to condensation or the like or by burning in the end faces of the semiconductor laser element due to deposition of the organic matter when they are used for a long time. It is thus desirable that the atmosphere in the interior of the package contains a low-moisture inert gas. In view of the price or the like, such a low-moisture inert gas is often nitrogen. A certain semiconductor laser element of a waveband such as 980 nm is known in which the burning due to the deposition of the organic matter can be prevented by oxygen. Thus, oxygen may be contained in the inert gas. Usually, a closure is seam welded on the main body of the package within the atmosphere of the above inert gas to manage the atmosphere.
Such a seam welding is broadly carried out within a glove box. The glove box may generally be in the form of a box-shaped airtight vessel on one side of which a glove panel is formed of plastic. A plurality of rubber gloves are mounted on the glove panel at its suitable locations. An operator can insert its hands into the gloves for actuating and/or operating the internal devices and instruments in an airtight manner.
Nitrogen always flows through the glove box to manage the component and moisture content of the gas within the glove box. If the introduction of nitrogen is ceased, the dew point in the glove box will increase due to moisture deposited on the glove box walls. To avoid such a problem, the flow rate of the nitrogen may be set relatively high, such as about 20 L/min. After the main body and closure of the package has been set, an internal seam welder is used to make sealing. An automated device may set and demount the semiconductor laser module before and after the welding process.
The first present invention provides a semiconductor laser module comprising:
a semiconductor laser element configured to produce laser light; and
a package being hermetically sealed and having an interior space that contains the semiconductor laser element, said package including a vent member that extends from said interior space to a space that is exterior to said package, wherein,
when unsealed, said vent member being configured to transport a low heat conduction gas between the interior space and the exterior, and
when sealed, said vent member being configured to prevent a flow of
gas between the interior space and the exterior.
The second present invention provides a semiconductor laser module comprising:
a semiconductor laser element configured to produce laser light; and
a package being hermetically sealed and having an interior space that contains the semiconductor laser element, said package includes
means for providing a low heat conduction gas to the interior space, and means for exhausting gas from the interior space.
The present invention also provides a method for producing a semiconductor laser module, comprising steps of:
disposing a semiconductor laser element in an interior space of a package;
sealing the package, except for a vent member that communicatively connects said interior space and an exterior space when open;
transporting a low heat conduction gas between the interior space and the exterior space through the vent member; and
hermetically sealing the vent member.